IN THE HEYDAY of the Byrd organization in Virginia, one of the strongest forces behind its near-total domination of the state's political machinery was a political legend himself -- E. Blackburn Moore, who died Tuesday in Winchester at the age of 83. For 30 years a neighbor and fellow apple grower of Harry Byrd Sr., "Blackie" Moore was a dedicated and effective point man for the organization and virtually all it stood for during the years of its tightest conservative grip on the state.

Mr. Moore's awesome powers grew out of a 35-year career in the Virginia legislature, including 18 years as speaker of the House of Delegates -- longer than anyone else in the history of the commonwealth. During this era of Old South resistance to change, pay-as-you-go fiscal policies and racial segregation, Speaker Moore ran the House with a soft voice and an iron fist -- rewarding political supporters of the Byrds and punishing enemies. Republicans in this latter category wound up with special assignments -- to committees that, as one member recalled, had not met since the Civil War.

Whatever resentment this autocratic rule generated, it worked. Mr. Moore's views tended to be shared and his counsel sought by any legislator with political ambitions. And however pervasive his influence over one of the oldest legislative chambers in the country turned out to be, even those who resented it recognized it as having been honestly acquired. Mr. Moore's love of Virginia was as strong as his devotion to its legislative process. The measured pace of Virginia's political transition toward membership in a "New South" is a mark of Speaker Moore's influence.